The present invention relates to an article storage facility, and more particularly to an article storage facility provided with a storage rack including a plurality of storage units that store articles and that are arranged in the vertical and horizontal directions, an vertically movable body guided to be allowed to move vertically by an vertical guide, and a transit body configured to move along a path defined along the storage rack.
With an article storage facility as described above, an article transport moves the vertically movable body to a position corresponding to one of the storage units with which a transfer is to be carried out through movement of the transit body and the vertical movement of the vertically movable body, and transfers (stores and removes) articles between the vertically movable body and the storage units. The article transport fetches articles from the storage units or stores articles in the storage units in this manner.
Such article storage facilities are provided with multiple article transports in the path in order to improve the transport capabilities. However, when multiple article transports are provided in the path, the movement ranges of two of the article transports will interfere with each other, and thus it is necessary to prevent the article transports from colliding with each other by limiting the movement of one of the article transports. Therefore, simply providing multiple article transports in the path may not achieve an improvement in the transport capabilities, as the multiple article transports cannot be moved with efficiency.
Accordingly, there is a conventional article storage facility provided with first and second article transports in the path, configured so that the first and second article transports can pass each other. The first and second article transports can therefore be moved with efficiency by causing them to pass each other when their respective movement ranges interfere with each other (for example, see JP H06-305514A).
In this conventional article storage facility, moving vertical guides past each other is made possible by disposing the vertical guide of the first article transport on one side in the lateral direction of the path and disposing the vertical guide of the second article transport on the other side in the lateral direction of the path. With respect to the transit bodies, the transit body of the first article transport and the transit body of the second article transport are disposed in the lateral direction in the path with a space provided therebetween, which makes it possible for the transit bodies to pass each other.
The vertically movable body is of a length that laterally spans the entire path, and is supported by the vertical guide capable of rotating, central to the vertical axis, between an article transfer orientation in which articles are transferred to or from a storage unit and a movement position used when moving through the path. In the article transfer orientation, the vertically movable body is positioned spanning the entire lateral length of the path by causing the lengthwise direction of the vertically movable body to match up with the lateral direction of the path, whereupon articles are transferred to or from a storage unit. Meanwhile, in the movement position, the dimension of the vertically movable body in the lateral direction of the path is reduced by causing the lengthwise direction of the vertically movable body to match up with the lengthwise direction of the path, and the vertically movable body is positioned so as not to come into contact with the vertically movable body and vertical guide of the opposing article transport in the lateral direction of the path, thereby making it possible for the vertically movable bodies to pass each other. Accordingly, the conventional article storage facility makes it possible for the first and second article transports to pass each other by switching the vertically movable body of the first article transport and the vertically movable body of the second article transport into movement positions.
The abovementioned conventional article storage facility makes it possible for the first and second article transports to pass each other while exchanging articles with storage units by switching the vertically movable bodies between an article transfer orientation and a movement position. However, it is necessary to add a structure for switching the vertically movable body between the article transfer orientation and the movement position, which leads to a more complicated configuration.
Furthermore, the conventional article storage facility makes it possible to transfer articles to or from storage units of storage rack provided on both sides of the lateral direction of the path by switching the vertically movable body to the article transfer orientation and thereby positioning the vertically movable body spanning the entire lateral length of the path. However, when the vertically movable body of one of the first and second article transports is switched into the article transfer orientation, the other article transport becomes unable to pass the other article transport. Therefore, while one of the first and second article transports is exchanging articles with a storage unit, it is necessary to constantly limit the movement of the other article transport, and thus the first and second article transports cannot be efficiently moved; it may therefore not be possible to improve the transport capabilities.